Results 221 to 230 of about 15,548 (262)

Refractive Index and Dispersion of the Benzene-Methanol System

The Journal of Chemical Physics, 1960
The refractive indices of the benzene—methanol system have been measured at 25° at seven wavelengths in the visible region. The electronic polarizability of benzene, methanol, and carbon tetrachloride have been calculated from the refractive indices of this system and those of the benzene-carbon tetrachloride system by use of the Böttcher equation. The
Wood, Scott E., Langer, Sidney, Battino, Rubin   +2 more
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The Index of Dispersion of Molecular Evolution: Slow Fluctuations

Theoretical Population Biology, 2000
The most simple neutral model of molecular evolution predicts that the number of substitutions within a lineage in T generations ought to be Poisson distributed. Therefore, the variance in the number of substitutions ought to equal the mean number. The ratio of the variance to the mean number of substitutions is called the index of dispersion, R(T ...
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Refractive Index and Dispersion

2014
The ISO 9802 Raw Optical Glass–Vocabulary and ISO 12123 Specification of Raw Optical Glass define refractive index as follows: “Ratio of the velocity of the electromagnetic waves at a specific wavelength in a vacuum to the velocity of the waves in the medium.” Dispersion denotes the effect that refractive index changes with wavelength.
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The Index-of-Dispersion Test Revisited

1996
In quantitative ecology the classical index-of-dispersion is widely used for testing the hypothesis of spatial randomness. However, spatial aggregation of individuals is often observed in field experiments, so that the test will frequently reject the hypothesis without indicating any alternatives.
D. Pfeifer, H. Ortleb, U. Schleier-Langer, H.-P. Bäumer   +3 more
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Note on the Poisson index of dispersion

Trabajos de Estadistica, 1956
Six1,x2,...,xn representan una muestra de N observaciones independientes de una variable de Poisson, se sabe [2] que el «indice de dispersion» $$z = \sum\limits_{i = 1}^N {(x_i - \bar x)^2 } /\bar x$$ tiene aproximadamente una distribucion χ2 con (N−1) grados de libertad.
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Refractive Index Determination using an Orthogonalized Dispersion Equation

Optical Interference Coatings, 1988
The refractive index n and thickness t of a thin-film coating can be determined from ellipsometric measurements of light reflected from the film. If data are taken over a broad range of wavelengths, then a range of values of n and t are obtained. The variation in n is expected and is a measure of the dispersion of the material.
C K, Carniglia, K N, Schrader, P A, O'Connell, S R, Tuenge   +3 more
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Dispersion of the refractive index of InP and ZnTe

Journal of Applied Physics, 1983
An analytical expression for the real part of the refractive index n near the fundamental absorption edge is given in terms of experimentally known quantities for a given semiconductor. It is derived from a quantum mechanical calculation of the complex dielectric constant which assumes the band structure of the Kane theory. The expression obtained is a
B. Jensen, A. Torabi
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Determination of the dispersion index for some fertilizers

Agricultural Meteorology, 1971
Abstract A number of experiences concerning the determination of the dispersion index for some fertilizers is here described. Measurement methods are described and the results are presented and discussed.
M. Colacino, R. Franco, F.M. Vivona
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Modal dispersion in multimode graded-index fibers

Applied Optics, 1975
A complete analysis of the propagation characteristics of a ray through an axially symmetric graded-index medium is carried out in the geometrical optics approximation. First, two constants of the motion are shown to exist for a ray propagating in an infinite medium.
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Robustness of the Estimator of the Index of Dispersion for DNA Sequences

Molecular Phylogenetics and Evolution, 1997
If substitutions in DNA sequences follow a Poisson process, the ratio of the variance in the number of substitutions to the mean number of substitutions (the index of dispersion) should equal 1. In this paper, the robustness of the commonly applied estimator of the index of dispersion in replacement sites and silent sites to various assumptions ...
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